Ultraflex B77 Single Lever Single Engine Top Mount Control with Trim

The Ultraflex B77 35313F is a black single-lever, dual-action top-mount control for one compatible outboard or sterndrive / I/O engine. It includes a pull-out warm-up function, positive lock-in neutral and a power trim switch in the handle grip. The optional X12 neutral safety switch can prevent in-gear starting.

Product Identification

• Brand: Ultraflex
• Product range: B77
• Product category: Mechanical marine engine control
• Available model(s): B77
• Manufacturer part number(s): 35313F
• Supplier catalogue code(s): 4-B77
• Store SKU(s): AF-4-B77
• Lever arrangement: Single lever
• Control action: Dual action
• Engine configuration: One engine
• Mounting: Top mount
• Application: Compatible outboard and sterndrive / I/O installations
• Material: Marine aluminium / black-painted die-cast control body
• Warm-up function: Pull-out handle disengages shift for engine warm-up
• Positive lock in neutral: Positive lock-in neutral provided
• Power trim switch: Power trim switch provided in the handle grip
• Neutral safety switch: Optional X12 neutral safety switch, part number 34543Q

What Is This Engine Control Used For?

The B77 combines throttle and shift operation in one lever. Moving the lever away from neutral first selects forward or reverse gear and then increases engine speed as the lever travel continues.

It is intended for compatible outboard and sterndrive / i/o installations. The control does not determine engine horsepower or gearbox capacity; the engine, gearbox, control cable and connection hardware must remain within their manufacturer ratings.

What Is Included?

The selected control is supplied with:

• Selected Ultraflex B77 control
• Positive lock-in-neutral mechanism
• Power trim switch integrated into the handle

Not included:

• Engine control cables
• Engine-end cable adaptors or clevises
• Optional neutral safety switch
• Connection kits not expressly stated as included
• Installation labour and boat-specific mounting reinforcement

Which Engines and Installations Are Compatible?

This control is intended for compatible outboard and sterndrive / i/o installations. Before ordering, confirm:

• The number of engines matches the control configuration
• The engine and gearbox use compatible mechanical throttle and shift cables
• The selected cable model is listed as compatible or has the correct Ultraflex connection kit
• The mounting position and handedness match the helm layout
• The panel provides sufficient clearance for the control mechanism and cable bends
• The lever can move through its complete range without contacting the steering wheel, instruments or structure
• The engine-end cable fittings and travel match the engine manufacturer requirements

Compatibility is determined by the complete control, cable, engine and gearbox arrangement rather than by the engine brand alone.

How Does the Control Operate?

• Lever configuration: Single lever
• Control action: Dual action
• Warm-up: Pull-out handle disengages shift for engine warm-up
• Throttle friction: Not provided
• Neutral locking: Positive lock-in neutral provided
• Power trim: Power trim switch provided in the handle grip

The warm-up function must only be engaged with the control in neutral. After warm-up, return the lever to the neutral position before re-engaging the shift mechanism.

Which Control Cables Are Compatible?

The following Ultraflex control cables connect without an additional conversion kit:

• C2
• C8
• MACHZero

The following cables require the stated connection kit:

• C5, C16 and MACH5: K35 connection kit, part number 34730U; sold separately
• C14 and MACH14: K51 connection kit, part number 32526N; sold separately

The following cables are not listed as compatible with this control:

• C22
• C36
• MACH36

Cable compatibility must be confirmed by the exact control model and cable model rather than by the general “33C” description alone. The engine-end adaptor required by the engine manufacturer is separate from the control-box connection kit.

Which Model Is Supplied?

• B77 / 35313F: Black powder-coated finish with chrome-plated lever
• Supplier catalogue code: 4-B77
• Store SKU: AF-4-B77

This listing covers the mechanical model identified above. Electronic, hybrid, alternate-handed or differently finished versions use separate Ultraflex model and part numbers unless expressly listed.

Dimensions and Fitment

• Use the current B73/B77 mounting drawing and dashboard cut-out template before installation

The dimensional drawing must be checked against the physical helm station before the panel is cut. Product photographs are not a mounting template. Allow additional clearance for cable end fittings, smooth cable bends and future servicing.

Optional Safety Switches and Accessories

• X12 neutral safety switch, part number 34543Q
• K35 connection kit, part number 34730U
• K51 connection kit, part number 32526N

The stated safety compliance is conditional: EN ISO 11547 when the optional X12 switch is installed. An optional switch is not included unless explicitly shown as a supplied component.

Construction and Design

• Marine aluminium / black-painted die-cast control body
• Single lever
• Dual action
• Top mount
• Not provided
• Pull-out handle disengages shift for engine warm-up
• Positive lock-in neutral provided
• Power trim switch provided in the handle grip
• Fully mechanical operation for the models included in this listing
• Designed for marine throttle and shift control applications

The control mechanism must be mounted to a rigid panel capable of supporting repeated lever loads. Cable routing and adjustment have a direct effect on shift engagement, throttle return and overall operating effort.

Installation and Use

Marine engine controls are safety-critical. Installation and adjustment should be carried out by a competent marine technician using the current Ultraflex instructions and the engine manufacturer’s cable-travel requirements.

Before installation:

• Confirm the exact control model and manufacturer part number
• Confirm the engine count, mounting position and handedness
• Identify the throttle cable and shift cable
• Obtain every required Ultraflex connection kit
• Check the panel cut-out and behind-panel clearance
• Inspect the control cables for corrosion, stiffness, kinks or damaged end fittings
• Place the engine and gearbox controls in their specified neutral and idle positions

After installation and adjustment, check that:

• Forward, neutral and reverse engage positively
• The throttle returns to idle without binding
• The warm-up function operates only as intended
• Any positive neutral lock engages and releases correctly
• Any trim switch operates in the correct direction
• The engine cannot start in gear when the optional safety switch is fitted
• Neither cable is under tension at the ends of lever travel
• The cables do not rub, kink or pass around bends tighter than their permitted radius
• All fasteners, pivots and cable retainers remain secure

The boat must not be used if the control is stiff, does not return to idle, fails to select neutral positively, allows unintended gear engagement or shows abnormal free movement.

Frequently Asked Questions

Does this control include the engine control cables?

No. Throttle and shift cables are supplied separately.

Is the neutral safety switch included?

No. Optional X12 neutral safety switch, part number 34543Q is optional unless a separate package explicitly states otherwise.

Can any 33C-style cable be fitted?

Not automatically. Use the exact Ultraflex cable list and connection-kit requirements shown in this listing.

Can the control be installed without checking the mounting drawing?

No. The panel cut-out, mechanism depth and cable routing must be checked before drilling.

Is a trim switch fitted?

Yes. A power trim switch is integrated into the handle. Engine-side wiring compatibility must still be confirmed.

Key Features

• Ultraflex B77 mechanical engine control
• Single lever
• Dual action
• One engine
• Top mount
• Compatible outboard and sterndrive / I/O installations
• Marine aluminium / black-painted die-cast control body
• Not provided
• Pull-out handle disengages shift for engine warm-up
• Positive lock-in neutral provided
• Power trim switch provided in the handle grip
• Optional X12 neutral safety switch, part number 34543Q
• EN ISO 11547 when the optional X12 switch is installed
• Manufacturer part number(s): 35313F
• Engine control cables supplied separately